I did consider it, Ratcatcher. I used to subscribe to several feeds from del.icio.us for library topics, and was often overwhelmed by the number- but I admit I didn’t often combinre tags the way you did in your example.

If you’d like to suggest some very specific del.icio.us-based feeds that wouldn’t muddy the search results’ relevance, I’d be interested in taking a look and discussing it with Frankie. The one you suggested (http://del.icio.us/rss/tag/libraries+tagging) looks interesting to me.